Without limiting the scope of the invention, its background is described in connection with antimicrobial surfaces for coating, paint, textile, water disinfection medium and other related subjects.
It is widely recognized that bacteria, fungi, and viruses can live on surfaces that appear to be visually clean. Inside corners, bolted joints, and some surfaces are just some examples of areas that are difficult to clean. Control of microbial growth and contamination is both vital and critical in every aspect of life and in every environment, ranging from food and beverage, dairy processing, pharmaceuticals, electronics, construction industry to healthcare. Microbes and germs are a daily threat, and bacterial fouling is an undesirable, preventable yet an often-occurring phenomenon.
Environmental surfaces contaminated with infectious agents play an important role in transmission of infections, and they are responsible for about 20% of the documented outbreaks of healthcare-associated infections, particularly those caused by multidrug-resistant species, which are difficult to treat, often leading to serious morbidity and mortality, extra costs, and excess length of hospital stay. They also may impair the quality of life of the patient with a hospital acquired infection even after treatment. One critical factor for transmission of infectious agents is the ability of microorganisms to survive on environmental surfaces. Microorganisms have strong abilities to survive on the surfaces of ordinary materials; some species of microorganisms, including drug-resistant strains, can stay alive for more than 90 days. Contaminated surfaces may serve as significant and important sources for cross-contamination and cross-infection. For example, a hospital outbreak of Methicillin-resistant Staphylococcus aureus (MRSA) was directly linked to a stretcher and a handheld shower; a Pseudomonas aeruginosa outbreak in a hematology-oncology unit was caused by contaminated surface cleaning equipment; and a norovirus outbreak at a long-term-care facility was associated with contaminated surfaces of case-residents' rooms, dining room tables, and elevator buttons. Recent studies showed that patients harboring multidrug-resistant bacteria such as MRSA and Vancomycin-Resistant Enterococci (VRE) could heavily contaminate their surrounding environment, and the contaminated surfaces could significantly increase the risk of transmission to subsequent room occupants.
Despite major medical advances, infectious diseases continue to be the third leading cause of death in the United States and the leading cause worldwide. The cleaning and disinfecting of environmental surfaces are recommended to reduce the risk of such infections. However, the disinfected surfaces can be re-contaminated rapidly.
The antimicrobial surfaces can help to control the wide spreading of infectious agents. If high-touch, high-risk surfaces are covered with antimicrobial coatings and/or antimicrobial paints that can provide effective antimicrobial functions, the surfaces will be protected between cleaning and disinfecting, and this has the potential to significantly reduce the risk of infections. Antimicrobial coating and paints can also be used outside of healthcare facilities to reduce the risk of community-acquired infections, and in flu seasons, reduce the risk of transmission of flu.
The antimicrobial coatings and paints industries are a huge market with a total value of $558,700,000 in 2012 in the United States alone. The United States market for antimicrobial coatings is forecasted to reach $978,700,000 by the year 2015, propelled by increasing demand for enhanced levels of health, sanitation and hygiene, particularly in end-use markets of indoor air quality and medical devices. The trend of strong growth pace is likely to continue in the future, spurred by growing urgency for infection control in hospitals, nursing homes, public places of all types, food and beverage dispensing systems, public transportation systems, and the like.
Textile materials are good media for growth of micro-organisms, particularly the drug-resistant bacteria in nosocomial infections, which have caused great concern to public health. Healthcare textiles usually include respirators, face masks, surgical gowns, isolation gowns, uniforms, patients' clothing, bedding materials, etc., which are used in healthcare facilities such as hospitals, medical and dental offices, public health clinics, assisted-living facilities, and home care. The humid and warm environments in textiles encourage the growth of the microbes. Infectious agents have strong abilities to survive on textiles, and some pathogens can survive for up to 90 days. Prevention of hospital acquired infections is therefore cost effective and achievable even when resources are limited. The currently used disposables can only serve as physical barriers. Once contaminated, they cannot inactivate the deposited microorganisms. During uses, the contaminated disposables can act as sources for direct or indirect transfer of infections. Furthermore, in the cases of leakages or “strike through”, the barrier functions will be totally lost and the users will face great danger. Otherwise, in the present world most of us are more conscious about our hygiene and cleanliness. In the cases of outbreaks of emerging infectious diseases, such as severe acute respiratory syndrome (SARS) or avian flu, the demand for antimicrobial textiles, particularly gowns and face masks, will increase dramatically because not only healthcare workers and patients but also the general public will need them for protection.
There accordingly remains a need for new compositions and methods to prevent microbial infection or transmission, including new compositions for antimicrobial surfaces with effective biocidal properties.